Process and apparatus for the manufacture of crank shafts



E. BECKER AND R. sucH'oPARE-K. PROCESS A ND AFFAHATUS FOR THEIVIANUFACTURE 0F CBANK SHAFTS.

VAPPLICATION FILED NOV. 29, i920.

Patented Apr. 25, 1922.

2 SHEETS-SHEET l.

Y FIGA I l l E. BECKER AND R. 'SUCHOPAREK. PROCESS AND APPARATUS FOR THEMANUFACTURE .0F CRA-NK SHAFT APPLICATION FILED Nov. 29, 19'20".

1,414,108. PanaApr.25,1922.

2 SHEETS-SHEET 2.

TNT.l ser l nnrorrnnoKnn, or KLADirdfGirnr/rANY, Ann niinorrsuorrornnmprknocrnrflrvy,

' j Annan KLADNG; @ECHO-SLOVAKIA; 1

rnoonss 'AND APPARATUS rorvTnEv MANU'raoTirnn or oiaANK sHArTs.. f

specification of Letters Patent.

l (GRANTED UNnnaTHnrRovIsronscr THE ACT or MARCH s, 1921, 41 STAT.. 1,.,13135 .To .all whom t may. concern'. l

Be it known that ive, Dr. Enron Bnoiinn, of Kladno, and "RDoiiiSUGHorlinnn,`V of Krocihlavy, near Kladno, `Czecho-Sloval'ra, citizensof Germany Aand-@ze'cho-Slovakia, respectively, have invented'new anduseful Improvements in the Processes andApparatuses for the Manufactureof Crank Shafts,

(for which r we haveiiled an application in Austria oet. isis',Germany,jN0v. ie, 1918, Patent No. 318,250; CzechofSlovakia,

' Y. May 15,1920; England, .nay Hi9', i920;

France, July 19, 1920; Switzerland, Julv- 2LH 1920; 'Hungary July i9,1920 ,f Italy July 2l, 1920, and the Netherlands, July 19, 1920,) ofwhich the following isa specification.

This invention relates to a process of and apparatus; for.v .themanufacturefof. crank vshafts,'the invention being equally applicable tocrank shafts having. one or more v.cranks formed thereon andin'dependent'of whether the cranks .are coplanar-,or lndifferentplanes.` l

Ithas already Vbeen proposed to produce crank.shaftsl by a process whichconsists in forcing a male. die into as teel matrix of suitablethioknessfor producing vthecrank while the crank webs are` formed by two .jaws orcheeks which are causedvto move at ri angles tothe vairis ofthe shaft.

pressing operation but the process is subiect to the disadvantage thatthe fibre of the materialfis torn away-andidisplaced and does not extendparallel to the longitudinal sides of the crank webs.

v It has also been proposed :to producecrank I' 40 shafts loyexertinganariallpressiire upon the end surface of a roundloar of steel of-dctermined length whilst simultaneously a male die is employed to bendthe shaft in a direc-A ytion at right angles to the axial` direction; In

vthis case the length ofthe steel bar is equal to the length of .thedeveloped shaft'lout the process, apart from the fact that only single Iso crankshaftscan he made thereby,`suffer`s from the 'disadvantage thatowing to-thedrawing of the 'outer "lihres no sharp edges crushed andfolded..A

Patented Apr. 25,1922, Application l'ed. November ,29, 1920;4 Serial No.427,197. 5

Moreover, in hoththe above proeessesthe blank must have -a crosssectionwhich is a in consequence expensive "rnacliine operations must beundertaken produce the finished shaft with a` 'c onsequent uneconoinicaleiny n ployinent of material.

`.The object; of the present invention'jisto provide a process whichwill he freefrom the' disadvantagesnoted above, andth'e-inventionConsists ina process for forming Y crank shafts which 'consists insimultaneously bending and upsetting the blank in order ,toV

producethe crank andcrank websin asingle Y operation.

lengthofthe blank must'he' longerfthan the length of the developed crankshaft butthe material `needed. for producinethejcrank shaft 1s thereforereduced a mlIl-imum.; j

Furthermore, .by' aj' process. in accordance According to `'thisprocess-,therefore with'the. invention ,the collars orshoulders Iprojecting from the/shaft at.; theyshaft jourf., nals and; crank pins.may be formed withV sharp edges so thattheyy need notice :ma

l i i chined from the. soli-d;` f The steel'fbar constituting tlieola'nkmay sol The Crank webs maybafdrmea 'pagina s@ .that they canals@befleftin theirough-in t ,i `which caseit isnecessary merely :to givea.'

finished *cutY ini thelathe, to lthe crank pins eedgshaft"'isuinalsvhehmay, be provided with asrnallcXoess of material, fmthis purjv posa,Astillfurther,advantage of the invervlftignv tions 0f working. l i

The accompanying drawings illustrate carrying out the invention. fFigure 1 1s a longitudinal. section-showing ance with the invention.Figure 2 isa plan.

lioV l Vlies inthe factfthatthebre inthe Crank v l ,websis oarallelwiththczed'gQ/S, thus po'vdf "ing the 'maximuinsecurity under any condi-Figures 3 and@ amorose-sectional v'iievvsif.k of the apparatus, theleft-hand crank'web .being shownfin elevationyin Figure?) andthe 95.'more or less diagrammatically one mode. ofy

Y at its centre the male die f, and two jaws each of which is formed intwo parts such as c and d.

The upper jaw parts d are pivotally connected to the lower parts 0 as,for example, by means of a pin c in such a manner that the jaw membersmay be openedout by pivoting the same about the pins e, the upper Vjawbeingshown partly open in the dot and dashiline of Figure 4L.

The jaws are mounted on the lower part a in such a manner that they arecapable fol! rotating in the direction oit the axis of the shaft and theupper surfaces ot the jaws are shaped to conform to theV concave undersurface of the upper part Z). One of. the jaws (Figure t) may haverecesses formed therein in order that when a multiple crank shaft is tobe produced` the cranks and lianges Y alreadyfformed may be suitablyarranged in Iposition as, for example, either all in one 35 plane orangularly disposed with reference to one another in planes 1209' 180 orother desired angle apart.

` In operation the jaws kare rotated outwards so that they assume theyposition shown in dotted lines in Figure l whereupon the upper jawparts are opened out and the blank which haslbeen bent to the form shownin Figure 6 is inserted between them and the jaws then closed.`

By the subsequent downward movement of the upper part o the jawvparts oand al are pressed so tirmly together that all escape of the material inthe subsequent bending and upsetting` operation is prevented.

Further Vdownward movement of the upper part causesthe jaws to movetowards each other until t-heyv assume the position shown in the fulllines in Figure l, thusY bending the shaft to form the crank whilstsimultaneously the male die 7 upsets the crank to produce the crank websto any required size, the shoulders or collars (limiting the journalsand any desired flanges being filled out simultaneously with the lillingout of the crank webs.

lt is to be further noted that according to the present invention whenproducing six throw crank shafts such as may be required in connectionwith aircraft, round steel bars ot 68 mm. diameter may be employedwhereas according to the hitherto proposed pro cesses for producing thesame shaft ot the same size it would be necessary to use a steel bar ota diameter of 18,0 tolQOO millimetres.

The invention is not to be limited to the precise'form of apparatushereinbeforeV de'- scribed by way out' example as the means adopted forproducing the combined bending and upsetting effect may be variouslymodi* lied to suit any practical requirementsthat may have to befulfilled. Y

What I claim is j l. A process for 'forming crank shafts which` consistsin bending a round workpiece to form elbows and simultaneously pressingout crank plates' thereon.

2. An apparatus iorcarrying out the process defined 1n claim lcomprising a male die operating to bend the elbows ot the crank` in theworkpiece, and axially rotatable jaws cooperating with the male dieadapted to lirmly grip the workpiece adjacent the elbow.

3. An apparatus Vfor carrying out the.r process defined in claim 1comprising amale' die operating to bend the elbows of the crank in theworkpiece, and axially rotatable jaws cooperating with the male dieformed to firmly grip the workpiece adjacent the elbow the engagingsurfaces of the male die and"` jaws being correspondingly curved.

ln testimony whereof we have signed our Y names to this specificationinthe presence of two subscribing witnesses. Y Y j f- DR.. ING. muon'BECKER. RDoLF sUoHornnK. Witnesses: j 'Y i f ING.'K. KUTHAN, ALoIsRnrPER.

